This invention relates to mammography and more particularly to a spot compression and magnification device for aiding in compressing a small area of the breast of a woman undergoing a mammographic examination to displace glandular structure and enhance the quality of the image made by the mammography x-ray apparatus.
The x-ray evaluation of the breast, known as mammography, can provide a sensitive and satisfactory means for examining women when screening for breast cancer, an abnormality which affects a significant percentage of the female population. The predictability of the results of the procedure, which is predicated upon an interpretation of the x-ray image produced, and thus the quality of the image, may in certain cases be indefinite and thus inconclusive. For example, many of the abnormal or suspicious soft tissue densities demonstrated are neither clearly benign nor malignant. Cancers, benign tumors, cysts, and asymmetrical areas of glandular tissue can all have similar appearances. Consequently, breast biopsies subsequent to mammographic examination using conventional compression of the breast disclose a relatively low positive yield for cancer, ranging from ten percent to thirty percent. Thus, it has been demonstrated that equivocal mammographic abnormalities require supplemental diagnostic procedures to avoid unnecessary breast biopsy.
One of the most useful additional procedures is a spot compression view which is performed with a small compression paddle to compress only a small area of the breast to increase the accuracy of the image and confidence of the interpretation, the small compression paddle being substituted for a larger conventional paddle. A spot compression view spreads apart glandular structures which can simulate a mass or hide the margins of a true mass. Such views can better define a mass seen on a routine view, and also distinguish abnormalities from those caused by superimposition of normal breast tissue. In the majority of cases a spot compression view shows the suspicious soft tissue density to be benign thereby eliminating unnecessary additional mammographic examination necessitating an additional dose of x-rays, and/or breast biopsy.
Conventional mammographic views utilize a large flat compression paddle which is pushed against the upper portion of the breast to compress the breast between the paddle and the imaging platform of the mammography apparatus. The smaller compression paddle is conventionally used to compress a small area over a potential abnormality in the breast when spot compression views are performed. All of the known compression paddles in the prior art are mechanically attached for use to the adjustable vertical column of the mammographic unit above the breast. When a suspicious area is located on an x-ray, the standard paddle is removed and replaced by the smaller spot compression paddle, which as aforesaid provides a localized compression and a higher quality view by moving normal glandular structure or tissue from dispositions which may be superimposed relative to the area of the breast which requires closer examination.
Many of the older mammographic units in operation do not have the capability of readily accepting spot compression paddles which, it is believed, are available only for the newer mammographic units. Because of the enormous capital expense required for acquiring such units, many hospitals and other diagnostic facilities having the older mammographic units have not made, and may be unable to make, such expenditures as are necessary. Additionally, even with those newer units that have spot compression paddles, because of the normal shape of a breast, i.e., the upper portion of the breast has a greater slope than the lower portion which is substantially horizontal, compression of the breast at the upper portion against the imaging platform may not provide as much clarity to the image as would appear to be the case were the breast to undergo additional spot compression from the lower portion. At least one manufacturer provides a rigid stool-like member for increasing the magnification of the image, but not for spot compression of the breast, the member being attachable to the image platform and having a large top portion on which the breast rests while the image is being made.